What does predestination mean in Ephesians 1:5?

Les explains that Paul defines adoption as it was practiced in Roman and Greek culture: a child born to the husband and wife was placed under tutors, educated and trained, and prepared to come in at an equal level with the father, perhaps for business. When he reached that point, he went through the rites of adoption. The Hebrew culture has something akin in the Bar Mitzvah when the boy reached age 14, but it was not the same category, because the Romans and Greeks were in the secular world preparing the child to be a co-worker in the business. Paul teaches that the moment we become a believer, we do not go through years of tutoring and training; we are immediately placed as an heir with the Father and the Son. Thus Ephesians 1:5 means we were predestinated not to heaven, not to hell, but as a believer to this position with Christ from day one, as a joint heir in the process of the adoption. Les also points to Ephesians 1:11, where believers have obtained an inheritance and are joint heirs with Christ; if you are a joint heir, the other parties are yours, and in the secular economy, if the other half passes off the scene, the heir ends up with it.